The research proposed for the next year includes resonance Raman (RR) and electrochemical studies of isolated photosynthetic pigments and quinones as well as chromatophore and reaction center (RC) preparations from photosynthetic bacteria. The RR experiments will be concerned with the effect of BChl-BPheo interactions on their respective spectra and the use of isotopically (deuterium) substituted BChl and BPheo to assist in the assignment of the vibrational spectra. A further effort will be made to characterize the RR spectra of the anion radicals of BChl and BPheo as a basis for future experiments using time resolved RR spectroscopy to identify these species in vivo. The RR spectrum of the anion radical of the ubiquinone (UQ) analogue, dimethyl-dimethoxybenzoquinone, will be investigated in more detail using the deep blue excitation wavelengths produced through stimulated Raman shifting of the second, third or fourth harmonics of the Nd:YAG laser as well as the fundamental or second harmonics of a dye laser by high pressure H2 or D2. Our preliminary experiments using surface enhanced resonance Raman spectroscopy to study cytochrome c and myoglobin at a Ag electrode will be extended to include photosynthetic preparations and model systems. The electrochemical experiments which are planned include studies of the effect of BChl-BPheo interactions on their redox potentials and electron transfer rates. In addition, thin-layer spectrochemical methods for studying the anion radicals of BChl, BPheo, and UQ in various solvents will be explored.